The present invention generally relates to medical devices. Specifically, the invention relates to communication between an implanted medical device and an external drug delivery device in wireless data communication thereof. More specifically, the invention relates to a system that automatically delivers analgesic and/or threshold reduction medications prior to the application of cardiac shock or drug delivery for pulmonary hypertension, for example, using RV pressure. The release of the drug is coordinated between the implanted device and the external device via the wireless communication system. The invention also provides remote management of a patient wherein drug delivery data from the external device and therapy information from the implanted device are transferred to a remote location using various methods of data transfer to enable physicians and caregivers to remotely review and monitor the patient as needed. In one aspect of the present invention, the drug delivery dose and frequency of treatment are preferably controlled via parametric modifications and adjustments of the implanted medical device. In yet another embodiment, the external drug delivery device is directly programmed overriding communication signals that initiate and call for drug delivery from the implanted medical device.
Current practice of implanting both a therapeutic medical device such as a cardiac pacemaker, defibrillator, etc., in conjunction with implantable drug pumps is cumbersome and expensive to manage. Further, for example, with a defibrillator and an implanted drug delivery device, one would need to run a catheter to deliver the drug in addition to leads for the defibrillator. Most implanted drug delivery devices known in the art, do not deliver drugs directly into the bloodstream.
The alleviation of cardioversion shock pain has been the subject of various patents in the prior art. Most of the pain-alleviating therapy, in conjunction with the delivery of cardioversion energy to the heart chamber is well known in the art. Further, the alleviation of pain through the operation of implantable drug dispensers for automatically, periodically, delivering a bolus of a pain-alleviating drug at the site in the body are also well known in the art. For example, U.S. Pat. Nos. 5,662,689 and 5,817,131 to Elsberry et al, disclose a methods and apparatus for alleviating cardioversion shock pain. The disclosures include an implantable cardioverter for providing cardioversion electrical energy to at least one chamber of a patient""s heart in need of cardioversion and applying a pain alleviating therapy at an appropriate site in the patient""s body prior to, or in conjunction with, the delivery of the cardioversion energy to the heart chamber to alleviate propagated pain perceived by the patient. The combined cardioversion and pain alleviating therapies are preferably realized in a single implantable, multi-programmable medical device or separate implantable cardioversion and pain control devices with means for communicating operating and status commands between the devices through the patient""s body.
U.S. Pat. No. 5,893,881 issued to Elsberry et al discloses a method and apparatus for alleviating cardioversion shock pain by delivering a bolus of analgesic. Specifically, the invention discloses an implantable cardioverter for providing cardioversion electrical energy to at least one chamber of a patient""s heart in need of cardioversion and applying a pain alleviating therapy at an appropriate site in the patient""s body prior to or in conjunction with the delivery of the cardioversion energy to the heart chamber to alleviate propagated pain perceived by the patient. The combined cardioversion and pain alleviating therapies are preferably realized in a single implantable, multi-programmable medical device or separate implantable cardioversion and pain control devices with means for communicating operating and status commands between the devices through the patient""s body.
U.S. Pat. No. 5,087,243 to Avitall discloses a myocardial iontophoresis device. An implantable iontophoretic delivery system for use in applying medicinal materials rapidly to specific subcutaneous tissue sites of interest in conjunction with an implanted defibrillator is disclosed which uses a subcutaneously situated pouch for supplying medication in conjunction with a pair of defibrillator electrodes connected to a power source. One of the electrodes is located proximately with respect to the tissue of interest and is designed to dispense the medication of interest utilizing controlled electrical pulses. The pouch is connected with the administering electrode of the electrode system via pumping mechanism.
U.S. Pat. No. 5,733,259 to Valcke et al discloses a method and apparatus for closed loop drug delivery. Specifically, a closed-loop drug delivery system uses patient response and rule based decision-making methods to achieve operator specified responses for diagnostic purposes. In the preferred embodiment, cardiac diagnosis is performed by pharmacologically stressing the heart by administration of an exercise simulating agent drug. In the preferred method, a protocol is defined, which preferably includes a target for a physiologic variable, such as heart rate, and a plan to achieve that target value. Preferably, the plan includes a specification of the desired rate of increase in that variable, such as the rate of increase in the heart rate per minute. The plan comprises the desired changes in the physiologic variable as a function of time.
U.S. Pat. No. 5,925,066 to Kroll et al discloses an atrial arrhythmia sensor with drug and electrical therapy control apparatus. The invention relates to an atrial arrhythmia sensor and drug-dispensing apparatus is disclosed. The apparatus comprises a multiphase, multistage intelligent system to monitor and treat atrial fibrillation. The apparatus includes atrial rate sensing means, cardiac pacing and antitachycardia pacing means, drug delivery means including a self-cleaning catheter line with multi-drug dispensing capability preferably operated using a dual pump arrangement and an iontophoretic device. The drug delivery system may also include a porous catheter to discharge drug into the atrium. The intelligent system includes a memory implemented logic (software) to continuously monitor the atrial rate and initiate a response of either cardiac pacing, antitachycardia pacing or drug dispensing based on preset cardiac activity parameters. The system also includes a medical history-recording feature.
U.S. Pat. No. 5,527,344 to Arzbaecher et al discloses a pharmacological atrial defibrillator and method. In this invention, a method and an implantable apparatus for automatically delivering a defibrillating drug to a patient upon detection of the onset of atrial fibrillation are disclosed. Atrial activity of a heart is detected and monitored. A delivery time is continuously computed and a delivery signal is emitted as a function of the monitored level of the atrial activity. When the delivery signal is emitted, an infusion pump discharges a defibrillating drug into the bloodstream of the patient. The atrial activity is also continuously monitored for computing a pacing time at which a pacing signal is emitted as a second function of the monitored level of atrial activity. When the pacing signal is emitted a pacer paces the atrium of the heart.
U.S. Pat. No. 5,135,480 to Bannon et al discloses a transdermal drug delivery device. More specifically, the invention relates to a transdermal device having a detachably mounted electrode with a first surface adapted for contact with human skin and through which a drug substance contained in the electrode passes to the skin under the influence of an iontophoretic or electro-osmotic force and a second surface which is electrically conducting, the electrode has a surface area in contact with the skin, in use, in the range 0.1 to 30 cm and a drug dissolved or dispersed in a hydrophilic medium at a concentration in the range 0.1 to 15% (w/v) based on the hydrophilic medium.
U.S. Pat. No. 6,091,989 to Swerdlow et al discloses a method and apparatus for reduction of pain from electric shock therapies. The invention discloses a method and apparatus for pretreating a patient prior to a therapeutic painful stimulus, comprising the application of pain inhibiting stimuli to a patient prior to an application of the therapeutic painful stimulus. Applying pain-inhibiting stimuli comprises the steps of sensing a need for the therapeutic painful stimulus, preparing to deliver the pain inhibiting stimuli to the patient prior to applying the therapeutic painful stimulus, and delivering the pain inhibiting stimuli to the patient prior to applying the therapeutic painful stimulus. The method and apparatus are embodied in a fully automatic; fully implantable, single or dual chamber atrial or ventricular cardioverter-defibrillators. The pain inhibiting prepulse method is intended primarily for use in conscious patients but may also be used in sleeping patients.
As can be seen from the prior art recited hereinabove, alleviation of cardioversion shock pain is an important consideration in cardiac therapy. However, there is a need for a closed loop controlled system to automatically deliver pain analgesics and/or threshold reduction medications prior to or contemporaneous with an atrial defibrillation shock or other drug delivery therapy that may be associated with discomfort or pain.
The present invention generally relates to a drug delivery device in wireless communication with an implanted medical device that preferably provides drugs transdermally prior to the delivery of therapy by the implanted device. The system is preferably telemetry or wireless communication-enabled to exchange data with the implanted device to thereby identify preshock events so that shock attenuation drugs could be delivered prior to an atrial defibrillation shock. More specifically, an iontophoretic drug delivery device is externally mounted on a patient""s body, and is interconnected by communication transmission channel with an implanted medical device in the patient. The external device and the implanted medical device are in a bi-directional data exchange using telemetry and equivalent wireless communication systems therebetween.
Further, the external iontophoretic drug delivery device and the implanted medical device are independently accessible to a programmer or an Independent Remote Monitor (IRM) external device for interrogation and reprogramming of parameters as needed. Furthermore, through either the IRM or a programmer, data may be transmitted to a PC for review by physicians or caregivers. Similarly, the data may be transferred to a server, which may be accessible to a plurality of users of the data for analysis, follow-up or research and development purposes.
Further, through media such as the Internet, intranet, extranet or World Wide Web, data from the server may be accessible by third parties, remotely to follow-up the patient and provide recommendations for adjustment or therapy as needed.
One aspect of the invention relates to the provision of one or more therapy regimens to the body, including two or more discreet medical devices, at least one of which medical devices is implanted into the living body and the other externally mounted, and being in bi-directional data communication and exchange with the implanted device.
Yet another aspect of the invention includes monitoring a condition of a living body on a continuous basis to provide a shock attenuation therapy before cardioversion electrical energy is applied to at least one chamber of a patient""s heart. Continuous monitoring and communication between the external device and the internal device coordinates the delivery of drug from the external device before shock is delivered by the implanted medical device. In this aspect of the invention, the external device and the internal device communicate and identify preshock conditions that indicate the imminence of cardioversion.
Yet another aspect of the invention includes a remote communication system in which an external drug delivery device is monitored and actuated to respond to indications of events that would trigger therapy by an implanted medical device, which may result in the perception of pain by the patient. The external device may be remotely programmed to deliver drugs transdermally immediately before or contemporaneous with the therapy. Similarly, the communication system would allow a remote review and programming of the implanted device. Further, amounts of pain reducing drugs to be delivered may be remotely adjusted to complement changes in cardioversion therapy.